LED to indicate activity on a USB port

Discussion in 'Embedded Systems and Microcontrollers' started by Ali.Soliman, Oct 2, 2012.

  1. Ali.Soliman

    Thread Starter New Member

    Sep 14, 2012
    5
    0
    Hi guys

    I am trying to use an LED to indicate activity on a uUSB port (flashing)

    I used a FET (FDV301N) connected to the VBUS and then to the LED

    Will this work?

    Is the VBUS always 5V when a USB device is connected or does it change value while device active/inactive.

    I attached a screenshot of my circuit.

    thanks you.
     
    • aac.png
      aac.png
      File size:
      28.6 KB
      Views:
      48
  2. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    7,387
    1,605
    VBUS is always 5 volts when plugged into the host. It's there to power your slave device.

    To indicate activity you have to add some code into your device (plus a pin to drive the LED).
     
    Ali.Soliman likes this.
  3. MrChips

    Moderator

    Oct 2, 2009
    12,440
    3,361
    When a USB device is plugged in, there is always activity on the bus.
    The USB controller constantly interrogates the device.
     
    Ali.Soliman likes this.
  4. Ali.Soliman

    Thread Starter New Member

    Sep 14, 2012
    5
    0
    Thank you guys.
    I appreciate all your help.

    Cheers.
     
Loading...